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Vortex identification based on the Liutex method and its effect on fish passage upstream

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Journal of Hydrodynamics 2024年第1期36卷 130-141页

作者： Chun-ying Shen Rui-guo Yang xiao-tao Shi Ming-ming Wang Shi-hua He Faculty of Electrical Power Engineering Kunming University of Science and TechnologyKunming650500China Hubei International Science and Technology Cooperation Base of Fish Passage China Three Gorges UniversityYichang443002China Shanghai Investigation Design and Research Institute Co.LtShanghai200434China

Fishway research is important for mitigating the fragmentation of river habitats caused by hydraulic *** vertical slit fishway is a broadly used fishway type because of its high efficiency and adaptability to water ***,the resulting vortex current disrupts the fish passage hence directly affecting fish *** study aims to accurately capture the vortex structure in the fishway and analyze the effect of vortex elements(vortex structure,vortex intensity,etc.)on *** conducted an analysis of the 3-D current flow field in the fishway through the utilization of an experimental model and the large eddy simulation(LES)***,we captured the vortex information in the fishway at different flow rates using the Liutex vortex identification method and investigated the effect of the vortex on fish *** results revealed that the structures inside the fishway pool occupy most of the room,however,the areas with higher vortex strength were primarily located in the vortex near the vertical seam and the mainstream,the vortex strength inside the fishway gradually increases with increasing flow,suppressing fish *** experienced significantly increased resistance when encountering strong *** suggests that the vortex may act as a physical barrier to fish *** findings highlight the potential negative effects of vortex on fish movement and reiterate the importance of understanding vortex dynamics for aquatic environmental *** an effective tool for identifying vortices in fluid flow,the Liutex method demonstrates features of vortex within the fishway,thereby providing important insights into the interaction between fluid dynamics and aquatic organisms.

关键词： Vertical slit fishway vortex identification method Liutex large eddy simulation(LES) fish experiment computational fluid dynamics

Lowering Sodium-Storage Lattice Strains of Layered Oxide Cathodes by Pushing Charge Transfer on Anions

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Energy & Environmental Materials 2024年第4期7卷 99-106页

作者： Na Li wen Yin Baotian Wang Fangwei Wang xiaoling xiao Jinkui Zhao Enyue Zhao Songshan Lake Materials Laboratory Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Spallation Neutron Source Science Center Institute of High Energy Physics Chinese Academy of Sciences College of Materials Science and Opto-electronic Technology Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences

Due to a high energy density,layered transition-metal oxides have gained much attention as the promising sodium-ion batteries ***,they readily suffer from multiple phase transitions during the Na extraction process,re... 详细信息

关键词： anionic redox reaction lattice strains layered oxide cathodes phase transitions sodium-ion battery

Toughening ultrastrong low-density steel by textured δ-ferrite lamellas

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Defence Technology（防务技术） 2024年第2期32卷 405-411页

作者： Bin Hu Guosen Zhu Guohui Shen Zheng Wang Qinghua wen xiao Shen Haiwen Luo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingXue Yuan Rd.30Beijing 100083China Shougang Research Institute of Technology Yangzhuang Street 69Beijing 100043China Steel Institute RWTH Aachen UniversityIntzestraße 152072AachenGermany

By both the Charpy V-notched impact and the projectile tests, we here investigated the dynamic fracture behavior of a recently developed ultrastrong lightweight steel comprising a hierarchical martensitic matrix, dispersed ultra-fine-retained austenite grains and oriented δ-ferrite lamellas, the latter being due to high Al and Si contents employed for low-density design. This steel shows a superior combination of specific ultimate tensile strength and impact toughness to other ultrastrong steels and has successfully arrested a real steel-cored bullet shot. These are attributed to the densely textured δ-ferrite lamellas that can deflect the propagating cracks until they are trapped and enclosed besides austenite-to-martensite transformation crack closure, leading to more energy consumed before failure. These results suggest a new pathway for toughening ultrastrong lightweight steels.

关键词： Ultrastrong and light steel d-Ferrite lamellas Crack propagation Toughness

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Ni-Catalyzed Enantioselective Difunctionalization of Alkynes to Azepine Derivatives Bearing a Quaternary Center and an Unprotected Imine

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Chinese Journal of Chemistry 2024年第8期42卷 873-878页

作者： Jian Long Zhiwu Lu xiao-Lin Li Peng Xue wen-Bo Liu Engineering Research Center of Organosilicon Compounds&Materials(Ministry of Education)and College of Chemistry and Molecular Sciences Wuhan UniversityWuhanHubei430072 China

Comprehensive Summary,The azepine ring is a prominent structural scaffold in biologically significant molecules. In this study, we present a Ni(II)-catalyzed asymmetric difunctionalization of alkynes, involving intermolecular regioselective arylation and intramolecular nitrile addition, enabling the synthesis of enantioenriched azepine derivatives. This reaction simultaneously installs an all-carbon quaternary stereocenter and introduces an unprotected imine functionality, showing great promise for subsequent transformations. The reaction exhibits good tolerance toward various functional groups, resulting in high yields and enantioselectivities. The synthetic utility of this methodology is further demonstrated through gram-scale synthesis and product derivatization. This research offers an efficient approach to the synthesis of seven-membered nitrogen heterocycles.

关键词： Nickel Asymmetric catalysis N-Heterocycles Alkyne functionalization Quaternary centers

High-temperature oxidation resistance of Si-coated C/SiC composites

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Rare Metals 2024年第9期43卷 4566-4572页

作者： Jie xiao hua-Yue Zhang Sheng-Kai Gong Hui-Bin Xu Hong-Bo Guo School of Materials Science and Engineering Beihang University Key Laboratory of High-Temperature Structure Materials and Protective Coatings (Ministry of Industry and Information Technology) Beihang University

In this paper, Si coatings were sprayed onto C/Si C composite substrates by atmospheric plasma spraying(APS). The high-temperature oxidation behavior of the substrate and coating at temperatures of 1100 and 1300 °C was also studied. The C/Si C ceramic matrix composite will be damaged seriously and even failed due to the oxidation of carbon fibers in matrix. The Si coating effectively improved the oxidation resistance of the C/Si C substrate in the high-temperature oxidation test. The effect of the thickness of the Si coatings on the oxidation resistance was investigated. The 150-μm coating is proved to enable the substrate to have the lowest oxidation weight loss and the best oxidation resistance after static oxidation for 5 h.

关键词： Carbon fiber Ceramic matrix composites (CMCs) Oxidation Plasma spray Si coating

The Q-index and Connectivity of Graphs

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Journal of the Operations Research Society of China 2024年第2期12卷 505-519页

作者： Peng-Li Zhang Li-hua Feng Wei-Jun Liu xiao-Dong Zhang School of Mathematical Sciences MOE-LSCSHL-MACShanghai Jiao Tong UniversityShanghai 200240China School of Mathematics and Statistics Central South UniversityChangsha 410083HunanChina

A connected graph G is said to be k-connected if it has more than k vertices and remains connected whenever fewer than k vertices are *** this paper,for a connected graph G with sufficiently large order,we present a tight sufficient condition for G with fixed minimum degree to be k-connected based on the *** result can be viewed as a spectral counterpart of the corresponding Dirac-type condition.

关键词： Q-index Minimum degree k-connected

Nomogram for predicting the risk of anxiety and depression in patients with non-mild burns

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World Journal of Psychiatry 2024年第8期14卷 1233-1243页

作者： Jie Chen Jian-Fei Zhang Xia xiao Yu-Jun Tang He-Jin huang wen-wen Xi Li-Na Liu Zheng-Zhou Shen Jian-hua Tan Feng Yang Department of Burns and Plastic Surgery The Second Affiliated HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421001Hunan ProvinceChina Department of Beauty Surgery Nantong Shenmei Medical Beauty ClinicNantong 226001Jiangsu ProvinceChina Department of Respiratory and Critical Care Medicine The Second Affiliated HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421001Hunan ProvinceChina

BACKGROUND Post-burn anxiety and depression affect considerably the quality of life and recovery of patients;however,limited research has demonstrated risk factors associated with the development of these *** To predict the risk of developing post-burn anxiety and depression in patients with non-mild burns using a nomogram *** We enrolled 675 patients with burns who were admitted to The Second Affiliated Hospital,Hengyang Medical School,University of South China between January 2019 and January 2023 and met the inclusion *** patients were randomly divided into development(n=450)and validation(n=225)sets in a 2:1 *** and multivariate logistic regression analyses were conducted to identify the risk factors associated with post-burn anxiety and depression dia-gnoses,and a nomogram model was *** Female sex,age<33 years,unmarried status,burn area≥30%,and burns on the head,face,and neck were independent risk factors for developing post-burn anxiety and depression in patients with non-mild *** nomogram model demonstrated predictive accuracies of 0.937 and 0.984 for anxiety and 0.884 and 0.923 for depression in the development and validation sets,respectively,and good predictive *** and decision curve analyses confirmed the clinical utility of the *** The nomogram model predicted the risk of post-burn anxiety and depression in patients with non-mild burns,facilitating the early identification of high-risk patients for intervention and treatment.

关键词： Burn Post-burn anxiety Depression Risk prediction Nomogram model

Associations between Geriatric Nutrition Risk Index,bone mineral density and body composition in type 2 diabetes patients

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World Journal of Diabetes 2024年第3期15卷 403-417页

作者： xiao-xiao Zhu Kai-Feng Yao Hai-Yan huang Li-hua Wang Department of Pediatrics The Second Affiliated Hospital of Nantong UniversityFirst People’s Hospital of Nantong CityNantong 226001Jiangsu ProvinceChina Department of Nursing The Second Affiliated Hospital of Nantong UniversityFirst People’s Hospital of Nantong CityNantong 226001Jiangsu ProvinceChina Department of Endocrinology The Second Affiliated Hospital of Nantong UniversityFirst People’s Hospital of Nantong CityNantong 226001Jiangsu ProvinceChina

BACKGROUND Type 2 diabetes mellitus(T2DM),a fast-growing issue in public health,is one of the most common chronic metabolic disorders in older *** and sarcopenia are highly prevalent in T2DM patients and may result in fractures and *** people with T2DM,the association between nutrition,sarcopenia,and osteoporosis has rarely been *** To evaluate the connections among nutrition,bone mineral density(BMD)and body composition in patients with *** We enrolled 689 patients with T2DM for this cross-sectional *** patients underwent dual energy X-ray absorptiometry(DXA)examination and were categorized according to baseline Geriatric Nutritional Risk Index(GNRI)values calculated from serum albumin levels and body *** GNRI was used to evaluate nutritional status,and DXA was used to investigate BMD and body *** forward linear regression analysis was used to identify the factors associated with BMD and skeletal muscle mass *** Of the total patients,394 were men and 295 were *** with patients in tertile 1,those in tertile 3 who had a high GNRI tended to be younger and had lower HbA1c,higher BMD at all bone sites,and higher appendicular skeletal muscle index(ASMI).These important trends persisted even when the patients were divided into younger and older *** GNRI was positively related to ASMI(men:r=0.644,P<0.001;women:r=0.649,P<0.001),total body fat(men:r=0.453,P<0.001;women:r=0.557,P<0.001),BMD at all bone sites,lumbar spine(L1-L4)BMD(men:r=0.110,P=0.029;women:r=0.256,P<0.001),FN-BMD(men:r=0.293,P<0.001;women:r=0.273,P<0.001),and hip BMD(men:r=0.358,P<0.001;women:r=0.377,P<0.001).After adjustment for other clinical parameters,the GNRI was still significantly associated with BMD at the lumbar spine and femoral ***,a low lean mass index and higherβ-collagen special sequence were associated with low BMD at all bone *** was negatively correlated with

关键词： Geriatric Nutrition Risk Index Bone mineral density Skeletal muscle mass Type 2 diabetes

Defect detection of light guide plate based on improved YOLOv5 networks

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Optoelectronics Letters 2024年第9期20卷 560-567页

作者： xiao Ming GONG Yefei WANG Hongding LU Mingli GAO hua School of Electrical Engineering Yancheng Institute of TechnologyYancheng 224007China School of Electrical and Automation Engineering Changshu Institute of TechnologyChangshu 215500China School of Physics and Electronic Engineering Northeast Petroleum UniversityDaqing 163318China Wuxi Novo Automation Technology Corporation Wuxi 214000China

Light guide plate(LGP)is a kind of material used in the backlight *** to improve the quality control of LGP has become the focus of research in the *** address issues such as low gray contrast and a high proportion of small target defects in LGP images,an improved you only look once version 5(YOLOv5)neural network based on multi-scale dilation convolution and a novel loss function is proposed.

关键词： network plate light

维普期刊数据库